Now i feel very Dumb!
All i had to do, was to enlist more crew and put them in the guns stations.
I tought it worked like in SH3, where if you see people on the guns station, they were
actually at the guns stations. You would have to put them in crew compartments and then they would go to the guns when called.
But here there are no crew quarters. So you have to put them on "the guns stations" even if they are not really there.
No mod needed after all! hehe.
Thanks Fifi.